Re: [PATCH v3 0/2] qspinlock: Introducing a 4-byte queue spinlock

[Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>]

On 01/31/2014 12:19 AM, Raghavendra K T wrote:
> On 01/30/2014 09:08 PM, Waiman Long wrote:
>> On 01/30/2014 03:55 AM, Raghavendra K T wrote:
>>> On 01/28/2014 11:49 PM, Waiman Long wrote:
> [...]
>                    from kernel/bounds.c:9:
>>> include/linux/log2.h: In function ‘__ilog2_u32’:
>>> include/linux/log2.h:34:2: error: implicit declaration of function
>>> ‘fls’ [-Werror=implicit-function-declaration]
>>> include/linux/log2.h: In function ‘__ilog2_u64’:
>>> include/linux/log2.h:42:2: error: implicit declaration of function
>>> ‘fls64’ [-Werror=implicit-function-declaration]
>>> include/linux/log2.h: In function ‘__roundup_pow_of_two’:
>>> .
>>> .
>>> [trimmed]
>>>
>>
>> The code will need to be compiled in either the latest linux tree as the
>> patches have dependency on some new memory barrier that are in 3.14.
>> Alternatively, you can compile with the latest tip tree.
>>
>> If you have already done that, please send me your config file so that I
>> can reproduce the compilation error in my build environment.
>>
>
> I did compile on latest linux tree which had barrier.txt. May be I 'll
> recheck if I am missing something obvious.
>
> Here is .config attached

An Update:
The reason for failure was that I was compiling for guest. and
CONFIG_PARAVIRT was enabled.